[Tom]

Originally Posted by Tiger Joe

you thought of increasing wheel size to lower your highway rpm is correct, but you forgot one other important aspect of physics- rotational weight. going bigger on tires also adds a lot of additional weight your motor needs to get moving all the time.

Correct. Decreases gas mileage and braking ability. On top of that I've never seen 37's that weren't very off road tread patterned, which deforms while driving more then normal which equals more more rolling resistance. Same thing with bigger sidewalls, its why semi's came up with super single tires to replace dual tires, less sidewall to flex so better gas mileage.